Gear shifting mechanism for motor vehicles



Nov. 15, 19138. s. NAMF'Al l 2,136,751

" GEAR SHIFTING MECHANISM FOR MOTOR VEHICLES Filed Dec. 16, 1936Z'ShsetS-Sheei l `emp/ i i iiiiii/ 6@ SMOM/74mm is, M. NAMPA Nav; l5,1938.

" A GEAR salmme uEcHANIsM Fon MOTOR vEHIcLEs Filed Dec. 16, 195e f 2sheets-shea 2 agg-ZZQOS I9/v a@ Patented Nov. 15, 1938 GEAR snlFrINGMEonAmsM Fon Moron vEmcLEs sum Michael Nampa, Detroit, Mich., assignorto Automatic Shifters, Inc., Richmond, Va., a corporation of VirginiaApplication December 16, 1936, Serial No. K116,195

20 Claims.

This invention relates to gear shifting mechanisms for motor vehicles.

In the prior patent of Edward 1G. Hill and Henry W. Hey, No. 2,030,838,there is disclosed a novel type of gear shifting mechanism for motorthings, functions in conjunction with other parts of the mechanism, toconnect both ends of the shifting motor to the source of vacuum, thusvacuum suspending." the piston in each of its gear positions. Thesubsequent admission Vof air to the end of the shifting motor cylinderadjacent y which the piston is arranged results in extremely rapidmovement of the piston of the motor.

In the structure of the patent, the vacuum suspension of the piston inits respective gear positions is present only when the vehicle clutch isdisengaged, and it was found desirable to maintain the vacuum suspensionof the motor piston in its respective gear positions regardless of theposition of the clutch elements, and at the same time, to prevent anyshifting operation from taking place except upon disengagement of theclutch. Such features are present in the structure of the copendingapplication of Edward G. Hill and Henry W. Hey, Serial No. 43,104, ledOctober 1st, 1935.

In the two prior structures ,referred to, the controlling of the mainvalves of the shifting motor is eiIected by controlling communicationbetween two control pipes and the'atmosphere, by means of a manualselector valve., The characteristics of such type of apparatus are suchthat the piston of the shifting motor is-vacuum suspended when both ofsuch control pipes are opened `to the atmosphere. In the copendingapplication referred to, a clutch .operated valve is provided whichfunctions to connect both of said control pipes and their associatedfluid pressure chambers to the atmosphere when the clutch is inengagement; thus retaining the vacuum suspension of the piston of theshifting motor and 4rendering the manual selector valve mechanismineffective for performing any shifting opera.- tions. When the clutchis disengaged, the two control pipes and their associated uid pressurechambers are disconnected from the atmosphere at the clutch operatedvalve and are connected to the source of vacuum, whereupon the apparatusis subject to manual control. 5

Thus the apparatus of the copending application functions to provide tworesults, namely, the maintenance of the vacuum suspension of the pistonof the shifting motor in its respective gear positions regardless of theposition of the clutch, and the prevention of a shifting operation untilafter the clutch is disengaged. In the structure of the copendingapplication, however, the clutch operated valve referred to is connectedfor direct actuation by the clutch, and accordingly operates between itstwo positions at a rate of movement corresponding to the rate at whichthe clutch pedal is depressed.

An important object of the present invention is to provide a gearshifting mechanism of the type disclosed in the patent and copendingapplication referred to having a clutch operated valve which performsthe functions of the corresponding valve of the copending application,but which snaps rapidly from one position to its other position uponmovement of the clutch pedal.

A further object is to provide a valve mechanism of this characterwherein the clutch valve remains in either of its positions untilsubstantial movement of the clutch pedal has taken place, and thereuponmoves extremely rapidly to its other position to perform its intendedfunction.

A further object is to provide a clutch operated valve in a gearshifting mechanism of this character wherein the actual movement-of thevalve y is eifected by the pressure of a spring, and whereinthe springpressure is built up byA movement of the clutch pedal to 'snap the valvefrom one of itsI positions to the other position when the pres- 40- sureof the spring which operates the valve is built up to a predeterminedextent.

Other objects and advantages of the invention will become apparentduring the course. of the following description. 45

In the drawings I have shown one embodiment of the invention. In thisshowing- Figure 1 is a perspective view of a portion of a motor vehiclegear set showing the shifting mechanism associated therewith,

Figure 2- is an end elevation of the selector valve, parts being shownin section,

Figure 3 'is a plan view of the selector handle device, I

Figure i is a sectionl on line 4-4 of Figure 1, 55

' through the man1: valve mechanism, taken on line Figure l'lgure 'I isa horiaontal sectional view taken 3-8 of Figure 6, and,

Figure 9 is a detail side elevation showing the clutch operated valveand one means of connecting such valve to the clutch pedal.

Referring-to the drawings, the numeral III designates a motor vehicletransmission having the usual shift rails adapted to be actuated by ahorizontal lever II having one end projecting from the transmissionhousing. Either of the shift rails may be selected for operation byproperly controlling a crossover motor I2. The particular means forselecting the shift rails and transmitting movement thereto forms nopart per se of the present invention and may be of any desired type as,for example, the type shown in the copending application of Edward D.Lasley, Serial No. 99,843, filed September 8, 1936.

The crossover motor I2, in accordance with the disclosure of the patentand copending apa valve mechanism to be described, which isv adapted toconnect the pipe I5 to the source of `vacuum to operate the motor I2 andthus transfill'1 the shift to the first and reverse gear shift r Thelever II is shifted by means of a main shifting motor indicated as awhole by the numeral I5. This motor comprises a cylinder I1 having apiston I8 therein, connected to one end o! a piston rod I9. The free endof this piston rod is connected as at to the outer end of the lever II.The motor I8 may be supported in any sutiable manner sofas to permitslight movement thereof necessary to compensate for the swingingmovement of the pivot pin 2l about the pivot axis of the lever II.

The perspective view in Figure l looks toward the forward end of themotor vehicle, and the forward and rear ends of the cylinder I1 areprovided with pipes 2I and 22 which. together with the pipe I5, lead toamain valve mechanism indicated as a whole by the numeral 23 andillustrated in detail in Figures 6, 7 and 8 of the drawings. Referringto Figure 6, it will be noted that the main valve mechanism comprises apreferably cast valve body 24 having three valves 25, 25 and 21i thereinprovided with vertical stems 23 extending upwardly through verticalpassages 29. Each of the valves 25, 25 and 21 is arranged in a chamber39 at the top of which is formed a valve seat 3| engageable by the upperface of the corresponding valve.l The lower faces of the valves aremovable downwardly into engagement with seats 32 formed in the upperends of the plugs 33. Each of these plugs is provided with a lowerinternal flange' 34 having an opening 35 therethrough for the admis-1vSion 0f all. A body of ltel'ing material 35 is 'arrangedbelow eachvalve u and is held in position by a screen or perforated plate 31.,Jl'he upper face of the valve body is providedwithapluralityofrecelooa39,andtheaere cesses are closed by an' elasticsheet 39. A cap 40 is secured in position over the sheet 39 as at 4|,the edge portions of the elastic sheet 39 thus being clamped between thecap 49 and the upper face of the valve body. The cap 49 is provided withchambers 42 corresponding in position to the respective chambers 38, thesheet 39 thus being divided into a plurality of diaphragms 43, 44 and 45to which are connected the upper ends of the stems of the respectivevalves 25, 25 and 21.

It will be apparent that. the chambers 38 communicate with therespective vertical openings 29, and these openings are connected by alongitudinal passage 45 extending into one end of the valve body. Thispassage communicates with a pipe 41 leading to the intake manifold 48 ofthe vehicle engine. Thus it will be apparent that vacuum is alwayspresent in the chambers 38 beneath the several diaphragms 43, 44 and 45.

'Ihe stem of the valve 25 is provided with a passage 49 communicatingwith the spaces on opposite sides of the diaphragm 43. The passage 49 isrelatively small in cross-sectional area and obviously affords constantrestricted communication between the corresponding diaphragm chamber 42and the vacuum passage 46. The other two chambers 42, above thediaphragms 44 and 45, also have restricted communication with the sourceof vacuum in a manner to be referred to, and the presence of vacuumabove either of the diaphragms 43, 44 or 45 creates a normal biastending to move the corresponding valve 25, 25 or 21 upwardly intoengagement with its seat 3I. The valve mechanism shown in Figures 6, 7and 8 forms the subject of the copending application of Edward D.Lasley, Serial No. 97,- 451, tiled August 22, 1936, and the feature ofnormally biasing the valves 25, 25 and 21 upwardly is fully disclosed insuch copending application. The valves are subject to rapid operation inview of the short distance each valve is required to travel, but ifdesired, a spring 58 may be arranged beneath each valveto increase itsspeed of movement from its lower position to its upper position.

As shown in Figure 7, the chamber 38 of the valve 25 communicatesthrough a lateral port 5I with the pipe I5, leading to the crossovermotor I2. I'he chambers 39 of the respective valves 25 and 21communicate through ports 52 with the pipes 22 and 2l, which lead to theopposite ends of the'motor cylinder I1. It will be apparent that whenthe valve 25 is in its upper position the pipe I5 is in communicationVwith the atmosphere, and when the valve 25 is in its-lower position, thepipe I5 communicates with the vacuum passage 48. Similarly, the oppositeends of the motor cylinder I1 communicate with the atmosphere or thevacuum passage 45 according to the positions `of the respective valves25 and 21.

Three pipes 53, 54 and 55 are utilized for controlling the operation ofthe main valves, and these pipes communicate with the chambers 42 -abovethe respective diaphragms 43, 44 and 45, as

shown in Figure 6. The pipes 54 `and 55 lead to an auxiliary valvedevice 55 having a valve (not shown) therein, connected by alink 51 tothe lever II. The valve device 55 conforms the functions of the valveshown in Figures 8, 9 and 10 of Patent No. 2,030,838, referred to above,and it -may be of the type shown'inFigures 5 and 6 of -the copendingapplication of Henry W. Hey, Serial No. 104.139, Illed October 5, 1936.I'he functionofthe'valved'evicellistoarrestthegear shifting' movement inneutral position when desired, and to effect the vacuum suspension ofthe shifting motor piston I5 in either of its gear positions. The valvedevice 55 includes passages connected at one 'end to the pipes 54 and 55and at their other ends to pipes 55 'and 59. In accordance with thedisclosure'ofcopending application Serial No. 104,139, the pipes'55 and59 are in constant communication with the respective pipes 54 and 55.

controlled ,by a valve 54 splined on a-rock shaft 55.

'I'he valve'vbody 5| is provided with a third passage 55 in which theinnerend of the shaft 55 is slidable and the passage 55 communicateswith the pipe 55. The shaft 55 is provided with an axial passage 51communicating with a lateral port 55 formed in the shaft 55 and movableinto communication with a port 59 formed in the valve body 5| when theshaft 55 is moved vlongitudinally toward the leftI of the position shownin Figure 4, in a manner to be described. As previously stated, thevalve 54 is splined on the shaft 55 and a spring 15 maintains the'valve54 on its seat.

The shaft 55 lis provided with a selector handle 1| operating in anH-slot 12 formed in a suitable housing 15. In accordance with thedisclosure of Patent No. 2,030,838, the handle 1| is movable in theH-slot 12 to partake of the same movement as a conventional gear shiftlever, the movement of the handle 1| to each lof its positions providinga gear ratio corresponding to the similar position of the usual gearshift lever.

As previously stated, the vacuum chambers 42 above the diaphragms 44 and45 (Figure 6) are adapted to have restricted communication with thesource of vacuum. The principal feature of the present invention is theprovision of a novel valve mechanism for controlling communicationbetween the vacuum chambers referred to and the atmosphere and vacuum.depending on whetherthe vehicle clutch is in engagement-5' Referring toFigure 6, it will be noted that the cap 45 is provided with restrictedpassages 14 communicating with each other at their upper ends anddiverging toward theirv lower ends' to communicate with the chambers 42above the respective diaphragms 44 and 45. The upper ends of thepassages 14 communicate with a pipe 15 leading to a clutch operatedvalve mechanism indicated as a whole by the numeral'15 and shown indetail in Figure 5. The valve mechanism 15 comprises a tubular housing11 in which is arranged a valve 15 provided with a pair of heads 15 and55 connected by a stem 5|. Another head 52 forms a part of the valve 15and is separated from the head 19 by a stem 55. This stem is drilledradially to provide a port 54' which communicates with an axial passage55 leading through the left hand end of the valve 15. as viewed inFigure 5. The valve body 11 is provided with a pair of ports 55 .and 51,the former of which communicates with 9|, and a detent 92 has itsinnerend adapted for engagement in the respective grooves 59 and 95,depending upon the position of the valve 15, as will be described. Thedetent 92 is urged inwardly by a spring 95. It will beobvious that thevalve 15 is adapted to assume either of two operative positions. andthat the spring pressed detent 92 resists movement of the valve awayfrom either of such two positions. In the position of the valve 15.shown in Figure 5, the pipe 15 communicates with the atmosphere throughthe port 54 and passage 55. In the other position of the valve 15, thestem 55 is moved to the right of the position shown in Figure 5, inwhich case the ports 55 and 51 communicate s with each other around thestem 5|.

The right hand end of the valve 15 as viewed in Figure 5 is providedwith an 'elongated diametrical slot 94, and the valve is provided with arelatively long axial opening 55. A n operating lever 95 for the valve15 is pivotally supported at any suitable point as at.5'| and has arounded end 95 extending through the slot 94 into the axial opening 95.A compression spring 99 is arranged between the end vof the lever andthe inner end of the axial opening 55. A similar spring |55 is arrangedin the outer end of the bore 95, with its inner end in engagement withthe end 95 of the lever, the outer end ofthe spring seating against apin |5|.

The other end of the lever 95 is' connected in any suitable manner to some portion of the clutch to be positively actuated thereby. Forexample, the lower end of the lever 95 may be pivotally connected as at|52 to one end of the link |53. The opposite end of this link may bepivotally connected as at |54 with the lower end of an arm |55 carriedby the conventionaiclutch pedal |55.

The operation of the apparatus is as follows:

Aside from the clutch opera valve shownin Figures 5and 9, the apparatusoperates in accordance with the disclosure of Patent No. 2,030,- 838 andthe several copending applications refer'red to, and need not bedescribed in detail.

Assuming that the clutch is disengaged, the valve 15 (Figure 5) willoccupy its operative position to the right of the position shown inFigure 5 with the detent 92-fin engagement with the groove 95. Undersuch conditions the ports 55 and 51 will communicate with each otheraround the valve stem 5|, and accordingly the chambers 42 above thediaphragms 44 and 45 will communicate with the intake manifold throughthe re-V the shaft 55 toward the left as viewed in Figure 4 opens thepassage 55 to the atmosphere through passage 51 and ports 55 and 55(Figures 2 and 4) Accordingly air will be admitted into the pipes 55 and55, while the pipe 55 will remain closed to the atmosphere. The -pipe 55communicates with the diaphragm chamber y42 above the diaphragm 45,while the pipe 55 communicates with the pipe 54, leading to thediaphragm chamber ofthe body of the main valve, and these pipes leadrespectively to the crossover motor casing I3 and to the rear end of thecylinder I1.

The crossover motor accordingly will be actu` ated to tend to select thelow and reverse gear shift rod for operation and assuming that theforegoing operation started with the parts in neutral position, thecrossover operation Will take place immediately upon movement of theselector handle 1I toward the left in the manner stated. Since theselector valve will maintain the pipe 59 closed, the pipe 55, whichcommunicates with the pipe 59 through the valve device 56, likewise willbe closed to the atmosphere. Since the pipe 55 leadsto the upper chamberof the diaphragm 45, such chamber will be closed to the atmosphere andair will be exhausted therefrom through its restricted passage 14. Thusthe valve 21 will remain in its upper position, and the pipe 2| (Figure7) will be opened to the atmosphere, thus maintaining atmos- .phericpressure in the forward end of the cylinand the forward end of thecylinder I1 will be connected to the source of vacuum through pipe 2Iand vacuum passage 46. ThusA the motor 'piston I8 will be vacuumsuspended in low gear position.

The movement of the selector handle 1I to the right and forwardly intosecond gear position, upon the next disengagement of the clutch, opensthe pipe 59 tothe atmosphere. This pipe will 'have been previouslyconnected to the atmosphere by the operation of the valve device 55.Thus the upper chamber of the diaphragm will remain in communicationwith the atmosphene, and the valve 21 vaccordingly will remain on itsseat 32. However, the selector valve 64, in second gear position, willhave closed Athe passage 52 to the atmosphere, and accordingly the upperchamber of thediaphragm 44 will be disconnect?! from the atmosphere andair will be exhaui ted therefrom through the associated passage 14. Thusthe valve 26 will move to its upper position, and the pipe 22 willconnect the rear end of the cylinder I1 to the atmosphere, and thepiston I8 will start to move forwardly. g

The sliding movement of the shaft incident to movement of the selectorhandle 1I to the' right, as viewed in Figure 4, will close the pipe 53to theatmosphere whereupon yair will be exhausted from the upper chamberof the diaphragm 43 through the valve stem passage 49. Thus thediaphragm 43 will move upwardly to its normal position and the valve 25will engage the seat 3I to connect the crossover -motor casing I3 to theatmosphere through pipe I5. When the shifting elements reach neutralposition, thereassociated valve 26l into engagement with its lower seat.Thereupon, the rear end of the cylinder I1 will be connected to theintake manifold through the vacuum passage 46, and the piston I8 will bevacuum suspended in second gear position.

The shift into high gear is made by moving the handle 1I directlyrearwardly from the second gear position. This operation does not affectthe crossover motor, and the second and high gear shift rail will remainselected for actuation. The rearward movement of the handle 1I controlsthe valves 26 and 21 and the shifting motor I6 in exactly the samemanner as for low gear, and accordingly it will be apparent that thepiston I8 will move rearwardly in the cylinder I1, which movementeffects the shift into high gear. When such gear position is reached,the valve device 56 will vacuum suspend the piston I8 in the same manneras for low gear.

When the transmission is to be shifted into reverse gear, the mainvalves 25 and 21 and the shifting lever I6 will function in the samemanner as for second gear. However, this shift requires movement of theselector handle 1I to the left, in which case the crossover to the rstand reverse gear shift rail will take place in neutral position,whereupon the piston I8 will continue to move forwardly. When thereverse gear position is reached, the valve device 56 will again providevacuum suspension of the piston I 8 in the manner described inconnection with second gear.

The foregoing operations have been described on the assumption that theclutch is disengaged prior .to each shifting operation. The valvemechanism shown in Figures 5 and 9 permits preselection to be made, andthe shifting operation cannot take place until after the clutch isdisengaged. In accordance with the previously described operations, itwill be apparent that each of tire valves 26 and 21 will move to itslower position when atmospheric pressure is present above thecorresponding diaphragm 44 or 45. So far as the selector valve 54 isconcerned, the valves 25 and 21 are separately operable. However, whenthe clutch is in normal engagement the valve 18 will occupy the positionshown in Figure 5, in which case the upper chambers of both diaphragr'ns44 and 45 will be opened to the atmosphere through ports 14, pipe 15,ports 86 and 84 and passage 85. Throughout the period of clutchdisengagement, therefore, both valves 26 and 21 remain in their lowerpositions, thus retaining the vacuum suspension of the piston I8 ineither of its gear positions. Under such conditions, it will be apparentthat the selector valve 64 is ineffective for controlling pressures inthe upper chambers of the diaphragms 44 and 45, andvaccordingly no gearshifting operation can' take place so long as the vehicle clutch is inengagement.

This operation not only prevents actual shifting of the gears duringclutch engagement, but also permits gear preselection to be practiced.It will be apparent'that upon disengagement of 21 are subject to controlby the selector valve 64 and the valve device 56, as soon as the clutchis disengaged, and the shift will be made in accordance with thepreselectedposition' of the handle 1|. `In the apparatus asillustrated;preselection may be practiced between any two positions ofthe handle 1| which are respectively forward and rear positions. Forexample, preselection may be made between rst and second gears, andsecond and high gears; between rst and reverse gears; and between highand reverse gears. The apparatus, of course, may be provided with apreselecting valve of the type shown in Figures 6 and 'l of Patent No.2,030,838, in which case preselection may be practiced between any twogear positions.

The functions described for the clutch operated valve in Figures 5 and 9correspond generally to the functions of the valve illustrated in Figure12 of copending application Serial No. 43,104, referred to above. Insuch construction.- the clutch operated valve is positively connected tothe clutch pedal for movement therewith, in which oase the ports of thevalve housing are progressively opened and closed and might be inclinedto result in a somewhat sluggish operation. In the present construction,it will be noted that the valve 18 is not positively connected to theclutch for operation thereby, movement being transmitted to this valvesolely through' the springs 99 and |00. Moreover, it will be noted thatthe detent 92 forms means for oiering sub- `stantial resistance tothemovement of the valve 40 Accordingly, it will be apparent that theclutch pedal |06 andlever 96 are adapted to partake of substantialmovement before effecting movementof the valve 18. Forexample, when thevehicle clutch is in engagement, the lever 96 will occupy the positionshown in Figure 5. When clutch disengaging movement is transmitted tothe pedal |06, the lever 96 will turn in a clockwise directionas viewedin Figure 5, and the upper .end of this lever will progressively buildup tension in the spring I 00. The parts are designed, including thedegree of tension ofthe springs 99 and |00` so that after completedisengagement of the clutch elements, the tension built up in the,`

spring |00 will be sumcient to overcome vthe resistance of the detent 92against sliding move'- -ment of the valve 18, and at such point thevalve 18 will snap to the right of the position shown in Figure 5, andthe detent will move across the stem 9| and engage the groove 90. Aspreviously t stated; this operation restores the controlling of thevalves 26 arid 21 to the selector valve 6.4 and the valve device 56.

Upon subsequent engagement of the clutch,`

the lever 96 will turn in a counter-clockwise direction, and the upperend of the lever will build up the tension of the spring 99. When theengagement of the clutch elements has been completed, the tension of thespring 99 will be built up to the point necessary toovercome theresistance of` the detent 92 to movement of the valve 18, whereupon thisvalve snaps to the left to return to the position shown in Figure 5,thus rendering the selector valve ineffective for controlling theoperation of the main valves 2'6 and Thus it will be apparent that theclutch operated valve 16 is important in improving the generalefficiency of the shifting apparatus, the valve 18 moving veryrapidlybetween its two positions and preventing the possibility of anyresulting sluggishness in the operation of the apparatus. Moreover, theclutch operated valve ports readily may be so designed as to permit anextremely rapid connection of the pipe 15 to the atmosphere or thedisconnection of such pipe therefrom at ing the lost motion between theclutch and the valve 18 is preferred for the reason that during therange of movement of the clutch pedal in which no movement is impartedto the valve 18, the spring tension is being built up so that the valve18 snaps very rapidly back and forth between its two positions.

Where the term clutch occurs in the claims it is to be understood thatthis expression is not limited to the clutch elements per se, but isintended to designate the conventional clutch unit asa whole includingthe operating elements usually associated therewith.

Where the claims define the main control valve mechanism as beingrendered inoperative by the means (valve mechanism 16) operable uponactuation of the clutch, it is to be understood that the expressioninoperative is intended to mean that the main valves 26fand 21 areincapable of being controlled or moved as distinguished from beingrendered merely ineffective for controlling the shiftingv motor, whichwould be true if a valve mechanism similar to the mechanism 16 should bearranged in the pipe 41 to disconnect the shifting motor from the sourceof vacuum.

It is to be understood that the form of the inthat various changes inthe shape, sizeand arrangementof parts may be resorted to withoutdeparting from the spirit ofv the invention or the scope of thesubjoined claims.

I claim: v

1. A gear shifting mechanism for a motor vehicle having a clutch and atransmission, comprising a power operated gear shifting mechanism,control mechanism for said shifting mechanism, and means operable uponactuation of the clutch for rendering said control mechanism inoperativewhen the clutch is engaged and oper- 6 ative when the clutch isdisengaged, said means having lost motion connection with the clutch.

2. A gear shifting mechanism for a motor vehicle having a clutch and atransmission, com- Drising a power operated gear shifting mechlanism,control mechanism for said shifting mechanism, and means operable uponactuation of the clutch for rendering said control mechanism inoperativewhen the clutch is engaged and operative when the clutch is disengaged,said means including a resilient motion transmitting device connectingvit to thel clutch.

3. A gear shifting mechanism for a. motor vehicle having a clutch andatransmission, comprising apower operated gear shifting mecha' nism, aplurality of control devices for controlling said mechanism, and meansoperable upon actuation of the clutch for controlling said devices, saidmeans including a resilient motion transmitting device connecting it tothe clutch.

4. A gear shifting mechanism for a motor vehicle having a clutch and atransmission, comprising a diierential pressure operated gear shiftingmechanism, a plurality of control devices for said mechanism, fluidpressure operated means for eiecting actuation of said control devices,and means operable upon actuation of the clutch for rendering saidpressure operated means inoperative when the clutch is in engagement,said last named .means having lost motion connection with 'the clutch.

A gear shifting mechanism for a motor vehicle having a clutch and atransmission, comprising a diierential pressure operated gear shiftingmechanism, a plurality of control devices for said mechanism, fluidpressure operated means for eiecting actuation-of said control devices,andmeans operable upon actuation of the clutch for rendering saidpressure operated means inoperative when the clutch is in engagement,said last named means including a.

it to the clutch. l

6. A gear shifting mechanism for a motor vehicle having a clutch and atransmission,` comprising a power operated gear shifting mechanism, aplurality of control devices for said mechanism, means for actuatingsaid control devices, and means operable upon actuation of the clutchfor controlling said control devices, said last named means comprising amovable element, means resisting the 'movement of said element, and alost motion connection for transmitting movement from the clutch to saidelement.

7. A gear shifting mechanism for a motor vehicle having a clutch and a`transmission, comprising a power operated gear shifting mechanism, aplurality oi'l control devices for said mechanism, means for actuatingsaid control deresilient motion transmitting device connecting vices,and means operable upon actuation ofthe clutch for controlling saidcontrol devices. said last named means comprising aimovable element,means resisting the movement of said element, and a resilient motiontransmitting device for transmitting movement from the clutch to saidelement.

8. A gear shifting'mechanism for a motor vehicle having a clutch and atransmission, comprislng a diilerential'f pressure operated gearshifting mechanism, a plurality of control valves for controlling saidmechanism, and means connected for controlling said control valves, saidlast named means comprising an auxiliary valve, means resisting movementof said valve, and a lost motion connection for transmitting movement tosaid auxiliary valve upon actuation of the clutch.

9. A gear shifting mechanism for a motor vehicle having a clutch andatransmission, comprising a diierential pressure operated gear shiftingmechanism, a plurality oi! control valves for controlling saidmechanism, and means connected, for controlling said control valves,said last named means comprising an auxiliary valve, means resistingmovement oi' said valve, and remeans, and a lost motion connection fortransmitting movement to said element upon actuation of the clutch.

1l. A gear shifting mechanism for a motor vehicle having a clutch and atransmssion,'com prising a diilerential pressure operated gear shiftingmechanism, a plurality of control valves for said mechanism, selectivelyoperable diierential pressure operated means for actuating sai-d controlvalves, means including a movable element connected for controlling theestablishment of differential pressure in said last named means, andresilient means for transmitting movement to said element upon actuationof the clutch.

12. A gear shifting mechanism for a motor vehicle having a clutch and atransmission, comprising a power operated gear shifting mechanism,v apluralityof control devices for said mechanism, diierential pressureoperated means for effecting actuation of said control devices, manualselecting means for controlling the differential pressures aii'ectingsaid pressure -operated means, means connected for rendering said manualselecting means ineii'ective for controlling differential pressures insaid pressure operated means, and lost motion means connecting said lastnamed means for movement upon actuation of the clutch.

13. A gear shifting mechanismvfor a motor vehicle having a clutch and atransmission, comprising a power operated gear shifting mechanism, aplurality of control devices for said mechanism, diierential pressure.operated means for effecting actuation of said control devices, manualselecting means for controlling the diiferential pressures affectingsaid pressure operated means, means connected for rendering said manualselecting means ineiective for controlling differential pressures insaid pressure operated means, and resilient means for transmittingmovement to said last named means upon actua-l tion of the clutch.

`14. A gear shifting mechanism for a motor vehicle having a clutch and atransmission, comprising a power operated gear shifting mechanism, aplurality of control devices for said mechanism, differential pressureoperated means for f eecting actuation of said control devices, manhiclehaving a clutch anda transmission, comprising a power operated gearshifting mechanism, a plurality of control devices for said mechanism,differential pressure operated means for. eiecting actuation of saidcontrol devices, manhicle having a' clutch and a transmission,comprising a power operated gear shifting mechanism, a plurality ofcontrol devices for said mechanism, fluid pressure operated means forselectively actuating said control devices, a source of non-atmosphericpressure, a conduit normally connecting said pressure operated means tosaid source, manual means for selectively connecting said pressureoperated means to the atmosphere. a valve operable for connecting saidconduit to the atmosphere independently of said manual means, meansresisting movement of said valve, andlost motion operating meansconnected to move said valve upon actuation of the clutch.

`17. A gear shifting mechanism for a motor vehicle having a clutch and atransmission, comprising a power operated gear shifting mechanism, aplurality of control devices for said mechanism, fluid pressure operatedmeans for selectively actuating said control devices, a source ofnon-atmospheric pressure, a conduit normally connecting said pressureoperated means to said source, manual means for selectively connectingsaid pressure operated means to the atmosphere, a valve operable forconnecting said conduit to the atmosphere independently of said manualmeans, means resisting movement of said valve, and resilient motiontransmitting means connected to move said valve upon actuation of theclutch.

18. A gear shifting mechanism for a motor vehicle having a clutch and atransmission, comprising a power operated gear shifting mechanism, aplurality of control devices for said mechanism, fluid pressure operatedmeans for seleci tively actuating said control devices, a source ofnon-atmospheric pressure, a conduit normally connecting said pressureoperated means to said source, manual means for selectively connecting 4said pressure operated means to the atmosphere,

a valve operable for connecting said conduit to `the atmosphereindependently of said manual means, said valve being provided with apair of spaced grooves, a spring pressed detent selectively.

engageable in said grooves to resist movement of said valve, and lostmotion operating means connected to move said valve upon actuation of vthe clutch.

19. A gear shifting mechanism for a motor vehicle having a clutch and atransmission, comprising a power operated gear shifting mechanism, aplurality of control devices for said mechanism, uid pressure operatedmeans for selectively actuating said control devices, a source ofnon-atmospheric pressure, a conduit normally connecting said pressureoperated means to said` source, manual means for selectively connectingsaid pressure operated means to the atmosphere, a valve operable forconnecting said conduit to the atmospherel independentlybf said manualmeans, said valve being provided with a pair oi spaced grooves, a springpressed detent selectively engageable in said grooves to resist movementof said valve, a lever having one end thereof adapted to be operatedupon actuation'of the clutch, and a pair of springs carried by saidvalve, the other end of said lever being arranged between said springsand operable therethrough for transmitting movement to said valve.

20. A gear shifting mechanism for a motor vehicle having a clutch and atransmission, comprising a power operated gear shiftingmechanism,control mechanism for said shifting mechanism, means movable between twopositions for rendering said control mechanism respectively operativeand inoperative, and snap acting means operable upon movement of theclutchbetween its engaged and disengaged positions for moving said rstnamed means respectively into its two positions.

SULO MICHAEL NAMPA.

